Information on cotton evapotranspiration (ET) during the seedling growth stage and under field conditions is scarce because ET is a difficult parameter to measure. Our objective was to use weighable lysimeters to meas...Information on cotton evapotranspiration (ET) during the seedling growth stage and under field conditions is scarce because ET is a difficult parameter to measure. Our objective was to use weighable lysimeters to measure daily values of cotton seedling ET. We designed and built plastic weighable micro-lysimeters (ML) that were 0.35 m deep with a soil volume of 6300 cm3. The soil core was obtained in-situ by pushing the ML well casing into the soil using a commercial soil sampler. The soil core was weighed with tension and compression type load-cells, where a change in mass of 18 g·d-1 was equivalent to a water evaporation of 1 mm·d-1. We compared load-cell measurements of changes in mass to values measured with a portable field scale by linear regression analysis, and the slope was equal to 1, indicating no statistical difference (P = 0.05) between the two measurements. We measured and compared seedling height, root length and leaf area of cotton plants in the ML with cotton plants in the surrounding area and this comparison showed that the ML used was suitable to measure cotton seedling ET for the first 30 days after seed emergence. The root mean squared error for crop height was 0.09 cm, for leaf area index (LAI) was 0.03 m2·m-2 and 6.5 cm for root length. Also, soil temperature at a 0.1 m depth was statistically (P = 0.05) the same in and outside the ML’s. For two planting dates, we measured daily values of soil water evaporation (E) and cotton seedling ET. The day following an irrigation event, E was ~ 9 mm d-1 and quickly declined the following days. Results showed that ML’s provide an accurate tool to measure water losses from the soil and cotton plants with a LAI of ≤0.2.展开更多
Changes in both soil organic C storage and soil respiration in farmland ecosystems may affect atmospheric CO2 concentration and global C cycle. The objective of this field experiment was to study the effects of three ...Changes in both soil organic C storage and soil respiration in farmland ecosystems may affect atmospheric CO2 concentration and global C cycle. The objective of this field experiment was to study the effects of three crop field management practices on soil CO2 emission and C balance in a cotton field in an arid region of Northwest China. The three management practices were irrigation methods(drip and flood), stubble managements(stubble-incorporated and stubble-removed) and fertilizer amendments(no fertilizer(CK), chicken manure(OM), inorganic N, P and K fertilizer(NPK), and inorganic fertilizer plus chicken manure(NPK+OM)). The results showed that within the C pool range, soil CO2 emission during the whole growing season was higher in the drip irrigation treatment than in the corresponding flood irrigation treatment, while soil organic C concentration was larger in the flood irrigation treatment than in the corresponding drip irrigation treatment. Furthermore, soil CO2 emission and organic C concentration were all higher in the stubble-incorporated treatment than in the corresponding stubble-removed treatment, and larger in the NPK+OM treatment than in the other three fertilizer amendments within the C pool range. The combination of flood irrigation, stubble incorporation and application of either NPK+OM or OM increased soil organic C concentration in the 0-60 cm soil depth. Calculation of net ecosystem productivity(NEP) under different management practices indicated that the combination of drip irrigation, stubble incorporation and NPK+OM increased the size of the C pool most, followed by the combination of drip irrigation, stubble incorporation and NPK. In conclusion, management practices have significant impacts on soil CO2 emission, organic C concentration and C balance in cotton fields. Consequently, appropriate management practices, such as the combination of drip irrigation, stubble incorporation, and either NPK+OM or NPK could increase soil C storage in cotton fields of Northwest China.展开更多
The study on the characteristics of spatial variability of soil nutrients and fertilizer recommendations in cotton field under certain conditions of agricultural management was conducted with GIS and systematic approa...The study on the characteristics of spatial variability of soil nutrients and fertilizer recommendations in cotton field under certain conditions of agricultural management was conducted with GIS and systematic approach for soil nutrient constrains. The results showed that of the spatial variability of soil nutrient was greatly related to the management condition of previous crops. Grid sampling and variable rate application technology (VRAT) were the tools that would hopefully increase fertilizer efficiency. The fertilizers were applied where they were needed and at proper rate. Balance fertilization demonstration showed that fertilizer recommendations according to the available nutrient level in soil could decrease fertilizer cost with 657.4 yuan / ha and increase seed cotton yield by 19.8%. A net profit of the balanced fertilization was 5314.9 yuan / ha higher than that of local fertilization practice.展开更多
In order to better serve cotton farmers,green prevention and control technologies of pests are formulated according to the sowing,seedling and adult stages of cotton from the aspects of ecological prevention and contr...In order to better serve cotton farmers,green prevention and control technologies of pests are formulated according to the sowing,seedling and adult stages of cotton from the aspects of ecological prevention and control,physical prevention and control,biological control and scientific use of pesticides,thus realizing green prevention and control of pests during the whole growth period of cotton.展开更多
[Objectives]This study was conducted to explore the characteristics of soil residual film pollution load in cotton fields in the Yellow River Delta,so as to effectively control soil film pollution.[Methods]Cotton fiel...[Objectives]This study was conducted to explore the characteristics of soil residual film pollution load in cotton fields in the Yellow River Delta,so as to effectively control soil film pollution.[Methods]Cotton field mulching film survey and residue monitoring were conducted in the Yellow River Delta area.[Results]The amount of mulching film residues in cotton fields in the Yellow River Delta was 37.7-128.7 kg/hm^(2),which had a significant increase compared with 5 years ago,and the differences between plots were large;and after straw was returned to the field,the soil residual film obviously gathered in the 20-30 cm soil layer.The residual film blocks with a size of more than 25 cm^(2) accounted for 62.6%,which was a relatively high proportion,indicating that soil pollution can be caused easily,and it is difficult to control.During a certain period of time,the soil residual film pollution may have a tendency to aggravate,and the ecological risk is higher.[Conclusions]This study has important theoretical and practical significance for improving soil quality in the region and ensuring the safety of cotton field ecosystem and environmental health.展开更多
Aphis gossypii is a globally distributed species and therefore has a highly variable life cycle.Populations of A.gossypii in northern China exhibit greater genotypic diversity and a broader host range,yet the details ...Aphis gossypii is a globally distributed species and therefore has a highly variable life cycle.Populations of A.gossypii in northern China exhibit greater genotypic diversity and a broader host range,yet the details of life cycles of different biotypes is still unclear.In this study,the Cytb and 16S gene regions of A.gossypii collected from 5 common summer hosts and 4 primary hosts were analyzed.A total of 57 haplotypes were obtained from 1 046 individual A.gossypii sequences.The sequence included 44 variable sites,27 of which were parsimony informative sites and 17 of which were singleton variable sites.The most frequent 3 haplotypes were found in 896 individuals,representing a total of 85.7% of all individuals and 36 haplotypes were found in 1 individual.A neighbor-joining tree was constructed using 21 haplotypes that were found in more than 2 individuals.Considering the individual host plant,5 biotypes were identified.Type 1 corresponded exactly to the cucurbit host-race and the other 4 biotypes were found as cotton host-races.Type 3 was the most abundant biotype in cotton fields in northern China.展开更多
Our study was conducted from August 2008 to March 2009 in the Houet province, western Burkina Faso. It consisted in the assessment of the constraints to the adoption by cotton growers of technologies promoted by the I...Our study was conducted from August 2008 to March 2009 in the Houet province, western Burkina Faso. It consisted in the assessment of the constraints to the adoption by cotton growers of technologies promoted by the IPM program through Farmers’ Field Schools in cotton-cereals-livestock systems. We did so by surveying a sample of 185 farmers trained in IPM and by describing farmers’ practices before and after the training in IPM. The results showed that the average dose of organic manure, NPK and urea used by famers after their training were respectively 3.8 tons/ha, 163 kg/ha and 65 kg /ha as compared with 2.4 tons/ha, 140 kg/ha and 51 kg/ha before the training. Regarding the use of pesticides, 94.6% of farmers used protection equipment during the sprayings after the training against 21.6% of them before the training. However, the average number of sprays did not vary significantly. It was 6 before the training and only 5 after. The botanical pesticides were used by 31% of farmers after the training as compared with 0% of users before the training in IPM. The training did not affect much crop yields. The constraints identified and classified according to their relative importance included the lack of agricultural equipment, and animals for ploughing, difficulties in inputs access, labor shortage, the lack of organic manure, and marketing problems. These technical, social and economic constraints have been analyzed and recommendations have been made to work them out.展开更多
文摘Information on cotton evapotranspiration (ET) during the seedling growth stage and under field conditions is scarce because ET is a difficult parameter to measure. Our objective was to use weighable lysimeters to measure daily values of cotton seedling ET. We designed and built plastic weighable micro-lysimeters (ML) that were 0.35 m deep with a soil volume of 6300 cm3. The soil core was obtained in-situ by pushing the ML well casing into the soil using a commercial soil sampler. The soil core was weighed with tension and compression type load-cells, where a change in mass of 18 g·d-1 was equivalent to a water evaporation of 1 mm·d-1. We compared load-cell measurements of changes in mass to values measured with a portable field scale by linear regression analysis, and the slope was equal to 1, indicating no statistical difference (P = 0.05) between the two measurements. We measured and compared seedling height, root length and leaf area of cotton plants in the ML with cotton plants in the surrounding area and this comparison showed that the ML used was suitable to measure cotton seedling ET for the first 30 days after seed emergence. The root mean squared error for crop height was 0.09 cm, for leaf area index (LAI) was 0.03 m2·m-2 and 6.5 cm for root length. Also, soil temperature at a 0.1 m depth was statistically (P = 0.05) the same in and outside the ML’s. For two planting dates, we measured daily values of soil water evaporation (E) and cotton seedling ET. The day following an irrigation event, E was ~ 9 mm d-1 and quickly declined the following days. Results showed that ML’s provide an accurate tool to measure water losses from the soil and cotton plants with a LAI of ≤0.2.
基金jointly funded by the National Basic Research Program of China (2006CB708401)the Doctor Subject Foundation of the Ministry of Education of China (20116518110002)
文摘Changes in both soil organic C storage and soil respiration in farmland ecosystems may affect atmospheric CO2 concentration and global C cycle. The objective of this field experiment was to study the effects of three crop field management practices on soil CO2 emission and C balance in a cotton field in an arid region of Northwest China. The three management practices were irrigation methods(drip and flood), stubble managements(stubble-incorporated and stubble-removed) and fertilizer amendments(no fertilizer(CK), chicken manure(OM), inorganic N, P and K fertilizer(NPK), and inorganic fertilizer plus chicken manure(NPK+OM)). The results showed that within the C pool range, soil CO2 emission during the whole growing season was higher in the drip irrigation treatment than in the corresponding flood irrigation treatment, while soil organic C concentration was larger in the flood irrigation treatment than in the corresponding drip irrigation treatment. Furthermore, soil CO2 emission and organic C concentration were all higher in the stubble-incorporated treatment than in the corresponding stubble-removed treatment, and larger in the NPK+OM treatment than in the other three fertilizer amendments within the C pool range. The combination of flood irrigation, stubble incorporation and application of either NPK+OM or OM increased soil organic C concentration in the 0-60 cm soil depth. Calculation of net ecosystem productivity(NEP) under different management practices indicated that the combination of drip irrigation, stubble incorporation and NPK+OM increased the size of the C pool most, followed by the combination of drip irrigation, stubble incorporation and NPK. In conclusion, management practices have significant impacts on soil CO2 emission, organic C concentration and C balance in cotton fields. Consequently, appropriate management practices, such as the combination of drip irrigation, stubble incorporation, and either NPK+OM or NPK could increase soil C storage in cotton fields of Northwest China.
文摘The study on the characteristics of spatial variability of soil nutrients and fertilizer recommendations in cotton field under certain conditions of agricultural management was conducted with GIS and systematic approach for soil nutrient constrains. The results showed that of the spatial variability of soil nutrient was greatly related to the management condition of previous crops. Grid sampling and variable rate application technology (VRAT) were the tools that would hopefully increase fertilizer efficiency. The fertilizers were applied where they were needed and at proper rate. Balance fertilization demonstration showed that fertilizer recommendations according to the available nutrient level in soil could decrease fertilizer cost with 657.4 yuan / ha and increase seed cotton yield by 19.8%. A net profit of the balanced fertilization was 5314.9 yuan / ha higher than that of local fertilization practice.
基金Supported by Cotton Innovation Team of Shandong Agricultural Industry Research System (SDAIT-07-011-09)Cash Crop Innovation Team Project of Zibo Agricultural Industry Research System。
文摘In order to better serve cotton farmers,green prevention and control technologies of pests are formulated according to the sowing,seedling and adult stages of cotton from the aspects of ecological prevention and control,physical prevention and control,biological control and scientific use of pesticides,thus realizing green prevention and control of pests during the whole growth period of cotton.
基金Supported by Coarse Cereals Innovation Team of Shandong Province Modern Agricultural Industry Technology System(SDAIT-15-11)Cotton Innovation Team(SDAIT-15-07)。
文摘[Objectives]This study was conducted to explore the characteristics of soil residual film pollution load in cotton fields in the Yellow River Delta,so as to effectively control soil film pollution.[Methods]Cotton field mulching film survey and residue monitoring were conducted in the Yellow River Delta area.[Results]The amount of mulching film residues in cotton fields in the Yellow River Delta was 37.7-128.7 kg/hm^(2),which had a significant increase compared with 5 years ago,and the differences between plots were large;and after straw was returned to the field,the soil residual film obviously gathered in the 20-30 cm soil layer.The residual film blocks with a size of more than 25 cm^(2) accounted for 62.6%,which was a relatively high proportion,indicating that soil pollution can be caused easily,and it is difficult to control.During a certain period of time,the soil residual film pollution may have a tendency to aggravate,and the ecological risk is higher.[Conclusions]This study has important theoretical and practical significance for improving soil quality in the region and ensuring the safety of cotton field ecosystem and environmental health.
基金supported by the National Natural Science Foundation of China(31572015)the National Special Transgenic Project of China(2016ZX08012-004)
文摘Aphis gossypii is a globally distributed species and therefore has a highly variable life cycle.Populations of A.gossypii in northern China exhibit greater genotypic diversity and a broader host range,yet the details of life cycles of different biotypes is still unclear.In this study,the Cytb and 16S gene regions of A.gossypii collected from 5 common summer hosts and 4 primary hosts were analyzed.A total of 57 haplotypes were obtained from 1 046 individual A.gossypii sequences.The sequence included 44 variable sites,27 of which were parsimony informative sites and 17 of which were singleton variable sites.The most frequent 3 haplotypes were found in 896 individuals,representing a total of 85.7% of all individuals and 36 haplotypes were found in 1 individual.A neighbor-joining tree was constructed using 21 haplotypes that were found in more than 2 individuals.Considering the individual host plant,5 biotypes were identified.Type 1 corresponded exactly to the cucurbit host-race and the other 4 biotypes were found as cotton host-races.Type 3 was the most abundant biotype in cotton fields in northern China.
文摘Our study was conducted from August 2008 to March 2009 in the Houet province, western Burkina Faso. It consisted in the assessment of the constraints to the adoption by cotton growers of technologies promoted by the IPM program through Farmers’ Field Schools in cotton-cereals-livestock systems. We did so by surveying a sample of 185 farmers trained in IPM and by describing farmers’ practices before and after the training in IPM. The results showed that the average dose of organic manure, NPK and urea used by famers after their training were respectively 3.8 tons/ha, 163 kg/ha and 65 kg /ha as compared with 2.4 tons/ha, 140 kg/ha and 51 kg/ha before the training. Regarding the use of pesticides, 94.6% of farmers used protection equipment during the sprayings after the training against 21.6% of them before the training. However, the average number of sprays did not vary significantly. It was 6 before the training and only 5 after. The botanical pesticides were used by 31% of farmers after the training as compared with 0% of users before the training in IPM. The training did not affect much crop yields. The constraints identified and classified according to their relative importance included the lack of agricultural equipment, and animals for ploughing, difficulties in inputs access, labor shortage, the lack of organic manure, and marketing problems. These technical, social and economic constraints have been analyzed and recommendations have been made to work them out.
